Simplified Fatigue Load Cases Assessment In Tension Leg Platform Floating Offshore Wind Structural Analysis

Floating offshore wind turbines (FOWTs) are considered a promising solution for wind energy harvesting in deep water, and optimized designs will bring the costs of FOWTs down and increase profitability. However, verifying the fatigue lifetime for the FOWT optimization model requires a large number of loading situations with computationally expensive response analyses. Fatigue damage calculated for six sets of simplified fatigue load cases (FLCs), with different combinations of turbine loads and wave loads, were compared using time-domain simulations in combination with Miner's Rule, which allows for the identification of optimal parameters in a lifetime perspective, and fair comparisons between the different contribution from loading of the wind turbine and environmental waves. The chosen FLC for fatigue damage verification of the floater scantling model in the present work is applicable for the preliminary design of Tension Leg Platform (TLP) FOWTs, where they can provide a starting design for the detailed design phases. The methodologies can be further extended to account for different FOWT concepts, additional design parameters, and other load combination cases.